Muraenesocidae, Kaup, 1859

Ebersole, Jun A., Cicimurri, David J. & Stringer, Gary L., 2019, Taxonomy and biostratigraphy of the elasmobranchs and bony fishes (Chondrichthyes and Osteichthyes) of the lower-to-middle Eocene (Ypresian to Bartonian) Claiborne Group in Alabama, USA, including an analysis of otoliths, European Journal of Taxonomy 585, pp. 1-274 : 189

Muraenesocidae indet. Fig. 69 E–F

Material examined

UNITED STATES OF AMERICA – Alabama • 3 otoliths; GLS otolith comparative collection (2 specimens), MSC 39064 .

Description

Shape best described as ovate (sensu Smale et al. 1995); height/length ratios approximately 60%. Length ranges from 6.5–7.5 mm. Margins smooth except for dorsal and posterodorsal margins, which may be coarsely lobed or crenulated. Anterior margin short and tapered. Anterodorsal margin slighted inflated, fairly steep, long. Dorsal margin short, irregularly lobed. Posterodorsal margin broadly rounded; posterior margin short, very slightly rounded outwardly, almost vertical. Posteroventral, ventral, anteroventral margins evenly but not deeply rounded. Inner face slightly convex, marked by conspicuous sulcus. Sulcus extending approximately 80% length of inner face; slightly flexed toward the posteroventral margin. Sulcus apparently undivided. Anterior upper margin of sulcus appears upwardly turning near anterodorsal margin. Posterior portion of sulcus more deeply excavated than anterior portion. Posterior end of sulcus rounded. Indications of possible crista superior. No ventral furrow visible. Outer face slightly convex, especially at center. Dorsal portion of outer face more undulating.

Remarks

Unfortunately, all three specimens are eroded, and it was difficult to ascertain detailed morphological features that would have assisted identification beyond the family level. Müller (1999) named Muraenesox rhomboideus from the Piney Point Formation of Virginia, which is Claibornian (Lutetian) in age.

Stratigraphic and geographic range in Alabama

This species was recovered only from the “upper” Lisbon Formation at site ACh-8. Bartonian, zones NP16 and NP17.

Figures

Fig. 69. Claiborne Group, “upper” Lisbon Formation, otoliths. A–B. Albula sp., MSC 562. A. Inner face (right sagitta). B. Dorsal view. — C–D. Pythonicthys colei (Müller, 1999), WSU CC 474. C. Inner face (left sagitta). D. Dorsal view. — E–F. Muraenesocidae Kaup, 1859, indet., MSC 39064. E. Inner face (left sagitta). F. Dorsal view. — G–H. Ariosoma nonsector Nolf & Stringer, 2003, MSC 39069. G. Inner face (left sagitta). H. Dorsal view. — I–J. Paraconger sector (Koken, 1888), MSC 39052. I. Inner face (right sagitta, broken on anterodorsal angle). J. Dorsal view. — K–L. Pseudophichthys sp., MSC 37059.2. K. Inner face (right sagitta). L. Dorsal view. — M–N. Rhynchoconger sp., MSC 37059.6. M. Inner face (left sagitta). N. Dorsal view. — O–P. Gnathophis meridies (Frizzell & Lamber, 1962), MSC 37059.XX. O. Inner face (right sagitta). P. Dorsal view. — Q–R. Myripristis sp., MSC 39047. Q. Inner face (right sagitta). R. Dorsal view. Scale bars: A–B =5 mm; C–R =2 mm.